Alert archive / California / Winter Storm Warnings in 2021
Winter Storm Warning 7, NWS San Diego, CA
NWS San Diego, CA issued this winter storm warning at Dec 26, 2021, 1:40 PM PST for Riverside County, San Bernardino County, San Diego County, California. It took effect at Dec 27, 2021, 12:00 PM PST. It was in force for 15 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Dec 26, 2021, 1:40 PM PST (21:40 UTC)
- In effect from
- Dec 27, 2021, 12:00 PM PST
- Expired
- Dec 28, 2021, 3:00 AM PST
- In force
- 15 hr
- Issued by
- NWS San Diego, CA
Counties Riverside County, CA, San Bernardino County, CA, San Diego County, CA
The radar
The Santa Ana Mts radar (KSOX), 122 km from the middle of the area, began a volume at 21:41 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
San Diego, CA (KNKX), launched 12:00Z, 9.7 hours before the alert went out and 145 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 2 J/kg
- Mixed-layer CIN
- -9 J/kg
- Mixed-layer LCL
- 690 m above ground
- 0-6 km bulk shear
- 78 kt
- 0-1 km storm-relative helicity
- -29 m²/s²
- 0-3 km storm-relative helicity
- 40 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
850 WWUS46 KSGX 262140 WSWSGX URGENT - WINTER WEATHER MESSAGE National Weather Service SAN DIEGO CA 140 PM PST Sun Dec 26 2021 CAZ055-056-058-270600- /O.UPG.KSGX.WS.A.0006.211227T2000Z-211228T1100Z/ /O.NEW.KSGX.WS.W.0007.211227T2000Z-211228T0800Z/ San Bernardino County Mountains-Riverside County Mountains- San Diego County Mountains- Including the cities of Crestline, Lake Arrowhead, Big Bear City, Big Bear Lake, Running Springs, Wrightwood, Idyllwild-Pine Cove, Julian, and Pine Valley 140 PM PST Sun Dec 26 2021 ...WINTER STORM WARNING IN EFFECT FROM NOON MONDAY TO MIDNIGHT PST MONDAY NIGHT... * WHAT...Heavy snow expected. Plan on difficult travel conditions, including during the evening commute on Monday. Damage to trees and power lines is possible. Total snow accumulations of 4 to 8 inches above 4500 feet, with localized amounts up to 16 inches above 6500 feet, are expected. Strong west to southwest winds 20 to 40 MPH with local gusts 60 to 80 MPH will occur at times. * WHERE...San Bernardino, Riverside and San Diego County Mountains. * WHEN...Noon Monday to midnight Monday night. * ADDITIONAL DETAILS...Be prepared for significant reductions in visibility at times due to snow, blowing snow, and fog. Some of the snowfall rates will be 1 to 2 inches per hour during the heaviest snows Monday afternoon. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning means severe winter weather conditions are expected. If you must travel, keep an extra flashlight, food, water and blankets in your vehicle in case of an emergency. $$ Maxwell
5 follow-up statements
288 WWUS46 KSGX 270437 WSWSGX URGENT - WINTER WEATHER MESSAGE National Weather Service SAN DIEGO CA 837 PM PST Sun Dec 26 2021 CAZ055-056-058-271400- /O.CON.KSGX.WS.W.0007.211227T2000Z-211228T0800Z/ San Bernardino County Mountains-Riverside County Mountains- San Diego County Mountains- Including the cities of Crestline, Lake Arrowhead, Big Bear City, Big Bear Lake, Running Springs, Wrightwood, Idyllwild-Pine Cove, Julian, and Pine Valley 837 PM PST Sun Dec 26 2021 ...WINTER STORM WARNING REMAINS IN EFFECT FROM NOON MONDAY TO MIDNIGHT PST MONDAY NIGHT... * WHAT...Heavy snow expected. Plan on difficult travel conditions, including during the evening commute on Monday. Damage to trees and power lines is possible. Total snow accumulations of 4 to 8 inches above 4500 feet, with localized amounts up to 16 inches above 6500 feet, are expected. Strong west to southwest winds 20 to 40 MPH with local gusts 60 to 70 MPH at times. * WHERE...San Bernardino, Riverside and San Diego County Mountains. * WHEN...Noon Monday to midnight Monday night. * ADDITIONAL DETAILS...Be prepared for significant reductions in visibility at times due to snow, blowing snow, and fog. Some of the snowfall rates will be 1 to 2 inches per hour during the heaviest snows Monday afternoon. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning means severe winter weather conditions and heavy Snow are expected. If you must travel, keep an extra flashlight, food and water in your vehicle in case of an emergency. For road condition information in California...enter 8 0 0 4 2 7 7 6 2 3 if inside california or 9 1 6 4 5 5 7 6 2 3 if outside California. $$
147 WWUS46 KSGX 271140 WSWSGX URGENT - WINTER WEATHER MESSAGE National Weather Service SAN DIEGO CA 340 AM PST Mon Dec 27 2021 CAZ055-056-272300- /O.CON.KSGX.WS.W.0007.211227T2000Z-211228T0800Z/ San Bernardino County Mountains-Riverside County Mountains- Including the cities of Crestline, Lake Arrowhead, Big Bear City, Big Bear Lake, Running Springs, Wrightwood, and Idyllwild-Pine Cove 340 AM PST Mon Dec 27 2021 ...WINTER STORM WARNING REMAINS IN EFFECT FROM NOON TODAY TO MIDNIGHT PST TONIGHT... * WHAT...Heavy snow expected. Plan on difficult travel conditions, including during the evening commute. Expect damage to trees and power lines as well. Total snow accumulations of 3 to 7 inches, with localized amounts up to 12 inches, are expected. Areas of winds southwest 30 to 40 mph with gusts to 60 mph. * WHERE...San Bernardino County Mountains and Riverside County Mountains. * WHEN...Noon today to midnight. * ADDITIONAL DETAILS...The more significant snow accumulations will be above 5000 to 5500 feet. The stronger winds will be near the mountain ridge tops and along the desert slopes of the mountains. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning for snow means severe winter weather conditions are expected. If you must travel, keep an extra flashlight, food and water in your vehicle in case of an emergency. For road condition information in California...enter 8 0 0 4 2 7 7 6 2 3 if inside california or 9 1 6 4 5 5 7 6 2 3 if outside California. $$ CAZ058-272300- /O.CON.KSGX.WS.W.0007.211227T2000Z-211228T0800Z/ San Diego County Mountains- Including the cities of Julian and Pine Valley 340 AM PST Mon Dec 27 2021 ...WINTER STORM WARNING REMAINS IN EFFECT FROM NOON TODAY TO MIDNIGHT PST TONIGHT... * WHAT...Heavy wet snow expected. Plan on difficult travel conditions, including during the evening commute. Expect damage to trees and power lines as well. Total wet snow accumulations of 4 to 6 inches are expected. Areas of winds west 30 to 40 mph with gusts to 60 mph. * WHERE...San Diego County Mountains. * WHEN...Noon today to midnight. * ADDITIONAL DETAILS...The more significant snow accumulations will be above 5000 to 5500 feet. The stronger winds will be near the mountain ridge tops and along the desert slopes of the mountains. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning for wet snow means severe winter weather conditions are expected. If you must travel, keep an extra flashlight, food and water in your vehicle in case of an emergency. For road condition information in California...enter 8 0 0 4 2 7 7 6 2 3 if inside california or 9 1 6 4 5 5 7 6 2 3 if outside California. $$ 17
497 WWUS46 KSGX 272135 WSWSGX URGENT - WINTER WEATHER MESSAGE National Weather Service SAN DIEGO CA 135 PM PST Mon Dec 27 2021 CAZ058-280600- /O.EXT.KSGX.WS.W.0007.000000T0000Z-211228T1100Z/ San Diego County Mountains- Including the cities of Julian and Pine Valley 135 PM PST Mon Dec 27 2021 ...WINTER STORM WARNING NOW IN EFFECT UNTIL 3 AM PST TUESDAY... * WHAT...Heavy snow expected. Plan on difficult travel conditions. Expect damage to trees and power lines as well. Total wet snow accumulations of 3 to 7 inches are expected. Areas of winds west 30 to 40 mph with local gusts to 65 mph. * WHERE...San Diego County Mountains. * WHEN...Until 3 AM Tuesday. * ADDITIONAL DETAILS...The more significant snow accumulations will be above 5000 to 5500 feet. The stronger winds will be near the mountain ridge tops and along the desert slopes of the mountains. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning for wet snow means severe winter weather conditions are occurring. If you must travel, keep an extra flashlight, food and water in your vehicle in case of an emergency. $$ CAZ055-056-280600- /O.CON.KSGX.WS.W.0007.000000T0000Z-211228T0800Z/ San Bernardino County Mountains-Riverside County Mountains- Including the cities of Crestline, Lake Arrowhead, Big Bear City, Big Bear Lake, Running Springs, Wrightwood, and Idyllwild-Pine Cove 135 PM PST Mon Dec 27 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT PST TONIGHT ABOVE 5500 FEET... * WHAT...Heavy snow expected. Plan on difficult travel conditions, including during the evening commute. Expect damage to trees and power lines as well. Total snow accumulations of 3 to 7 inches, with localized amounts up to 12 inches, are expected. Areas of winds southwest 30 to 40 mph with local gusts to 65 mph. * WHERE...San Bernardino County Mountains and Riverside County Mountains. * WHEN...Noon today to midnight. * ADDITIONAL DETAILS...The more significant snow accumulations will be above 5000 to 5500 feet. The stronger winds will be near the mountain ridge tops and along the desert slopes of the mountains. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning for snow means severe winter weather conditions are occurring. If you must travel, keep an extra flashlight, food and water in your vehicle in case of an emergency. $$ Maxwell
697 WWUS46 KSGX 280508 WSWSGX URGENT - WINTER WEATHER MESSAGE National Weather Service SAN DIEGO CA 908 PM PST Mon Dec 27 2021 CAZ055-056-280800- /O.CON.KSGX.WS.W.0007.000000T0000Z-211228T0800Z/ San Bernardino County Mountains-Riverside County Mountains- Including the cities of Crestline, Lake Arrowhead, Big Bear City, Big Bear Lake, Running Springs, Wrightwood, and Idyllwild-Pine Cove 908 PM PST Mon Dec 27 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT PST TONIGHT ABOVE 5500 FEET... * WHAT...Heavy snow occurring. Plan on difficult travel conditions. Damage to trees and power lines is possible. Additional snow accumulations of 2 to 4 inches are expected. * WHERE...San Bernardino County Mountains and Riverside County Mountains. * WHEN...Until midnight. * ADDITIONAL DETAILS...Be prepared for significant reductions in visibility at times. The more significant snow accumulations will be above 5000 feet. The stronger winds will be near the mountain ridge tops and along the desert slopes of the mountains. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning for snow means severe winter weather conditions are occurring. If you must travel, keep an extra flashlight, food and water in your vehicle in case of an emergency. For road condition information in California...enter 8 0 0 4 2 7 7 6 2 3 if inside california or 9 1 6 4 5 5 7 6 2 3 if outside California. $$ CAZ058-281100- /O.CON.KSGX.WS.W.0007.000000T0000Z-211228T1100Z/ San Diego County Mountains- Including the cities of Julian and Pine Valley 908 PM PST Mon Dec 27 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 3 AM PST TUESDAY ABOVE 5500 FEET... * WHAT...Heavy wet snow occurring. Plan on difficult travel conditions. Expect damage to trees and power lines as well. Additional wet snow accumulations of 4 to 6 inches are expected. * WHERE...San Diego County Mountains. * WHEN...Until 3 AM Tuesday. * ADDITIONAL DETAILS...Be prepared for significant reductions in visibility at times. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning for wet snow means severe winter weather conditions are occurring. If you must travel, keep an extra flashlight, food and water in your vehicle in case of an emergency. For road condition information in California...enter 8 0 0 4 2 7 7 6 2 3 if inside california or 9 1 6 4 5 5 7 6 2 3 if outside California. $$
058 WWUS46 KSGX 281039 WSWSGX URGENT - WINTER WEATHER MESSAGE National Weather Service SAN DIEGO CA 239 AM PST Tue Dec 28 2021 CAZ058-281145- /O.EXP.KSGX.WS.W.0007.000000T0000Z-211228T1100Z/ San Diego County Mountains- Including the cities of Julian and Pine Valley 239 AM PST Tue Dec 28 2021 ...WINTER STORM WARNING WILL EXPIRE AT 3 AM PST EARLY THIS MORNING ABOVE 5500 FEET... The winds are weakening and the heaviest snow has ended, however light showers will persist through today. $$ 12
The office that day
Everything else NWS San Diego, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 26, 12:58 AM PST | Areal Flood Advisory | SGX | Orange, Riverside, San Bernardino | 3 hr |
| Dec 26, 2:33 AM PST | Gale Watch | SGX | 11 hr | |
| Dec 26, 3:25 AM PST | Wind Advisory | SGX | Riverside, San Bernardino, San Diego | 9 hr |
| Dec 26, 12:03 PM PST | High Wind Warning | SGX | Riverside, San Bernardino, San Diego | 32 hr |
| Dec 26, 1:42 PM PST | Gale Warning | SGX | 30 hr |
Nearby
Winter Storm Warnings in California, 2021Every winter storm warning in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.